Flexible printed circuit boards comprise a flexible film made of insulating material with adhesive conductive connections and serve the purpose of mechanically fastening and electrically connecting electronic components. Contact surfaces are attached to surfaces of the flexible printed circuit boards, a flawless condition of the contact surfaces being a prerequisite for a subsequent faultless usage of the flexible printed circuit board.
A process chain for manufacturing, further processing and mounting a flexible printed circuit board comprises a plurality of individual process steps which are linked with each other through various handling and/or transport steps. In particular manual and/or machine handling and/or transport steps can cause damage to the contact surfaces due to scratching or contaminating the contact surfaces as a result of hand perspiration, oil or grease and particles present on a support surface. Flexible printed circuit boards damaged or contaminated in this manner are not suitable for further processing.
For protecting contact surfaces from adverse effects due to contamination or damage, protective adhesive stickers are provided which are affixed to the contact surfaces. On removal of the protective stickers, residues of an adhesive layer can remain on the contact surface, resulting in a contamination of the contact surface. Furthermore, separate protective arrangements for use in individual manufacturing plants as well as complex handling steps in the form of manual handling wearing protective gloves or additional, complexly designed gripper systems in the case of machine handling are known. The above-mentioned protective measures involve high expenditure in terms of plants and/or time and are therefore cost-intensive.
Furthermore, there is a risk of damage and/or contamination of the contact surfaces after finishing one process step and during subsequent handling or transport of the flexible printed circuit boards.